diff options
| author | David Daney <ddaney@caviumnetworks.com> | 2010-10-14 11:32:33 -0700 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2010-10-29 19:08:53 +0100 |
| commit | 949e51bea342da838be5295628e4a7ada8bae833 (patch) | |
| tree | 8967391768d4da3a99a2adf85e0834e0fa7a2009 /arch/mips/include/asm/processor.h | |
| parent | 18d693b3598fdebdd5c65a613221793456a7ce45 (diff) | |
MIPS: Make TASK_SIZE reflect proper size for both 32 and 64 bit processes.
The TASK_SIZE macro should reflect the size of a user process virtual
address space. Previously for 64-bit kernels, this was not the case.
The immediate cause of pain was in
hugetlbfs/inode.c:hugetlb_get_unmapped_area() where 32-bit processes
trying to mmap a huge page would be served a page with an address
outside of the 32-bit address range. But there are other uses of
TASK_SIZE in the kernel as well that would like an accurate value.
The new definition is nice because it now makes TASK_SIZE and
TASK_SIZE_OF() yield the same value for any given process.
For 32-bit kernels there should be no change, although I did factor
out some code in asm/processor.h that became identical for the 32-bit and
64-bit cases.
__UA_LIMIT is now set to ~((1 << SEGBITS) - 1) for 64-bit kernels.
This should eliminate the possibility of getting a
AddressErrorException in the kernel for addresses that pass the
access_ok() test.
With the patch applied, I can still run o32, n32 and n64 processes,
and have an o32 shell fork/exec both n32 and n64 processes.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1701/
Diffstat (limited to 'arch/mips/include/asm/processor.h')
| -rw-r--r-- | arch/mips/include/asm/processor.h | 40 |
1 files changed, 19 insertions, 21 deletions
diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index 0d629bb93cb..ead6928fa6b 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -50,13 +50,10 @@ extern unsigned int vced_count, vcei_count; * so don't change it unless you know what you are doing. */ #define TASK_SIZE 0x7fff8000UL -#define STACK_TOP ((TASK_SIZE & PAGE_MASK) - SPECIAL_PAGES_SIZE) -/* - * This decides where the kernel will search for a free chunk of vm - * space during mmap's. - */ -#define TASK_UNMAPPED_BASE ((TASK_SIZE / 3) & ~(PAGE_SIZE)) +#ifdef __KERNEL__ +#define STACK_TOP_MAX TASK_SIZE +#endif #define TASK_IS_32BIT_ADDR 1 @@ -71,28 +68,29 @@ extern unsigned int vced_count, vcei_count; * 8192EB ... */ #define TASK_SIZE32 0x7fff8000UL -#define TASK_SIZE 0x10000000000UL -#define STACK_TOP \ - (((test_thread_flag(TIF_32BIT_ADDR) ? \ - TASK_SIZE32 : TASK_SIZE) & PAGE_MASK) - SPECIAL_PAGES_SIZE) +#define TASK_SIZE64 0x10000000000UL +#define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64) + +#ifdef __KERNEL__ +#define STACK_TOP_MAX TASK_SIZE64 +#endif + -/* - * This decides where the kernel will search for a free chunk of vm - * space during mmap's. - */ -#define TASK_UNMAPPED_BASE \ - (test_thread_flag(TIF_32BIT_ADDR) ? \ - PAGE_ALIGN(TASK_SIZE32 / 3) : PAGE_ALIGN(TASK_SIZE / 3)) #define TASK_SIZE_OF(tsk) \ - (test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE) + (test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64) #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR) #endif -#ifdef __KERNEL__ -#define STACK_TOP_MAX TASK_SIZE -#endif +#define STACK_TOP ((TASK_SIZE & PAGE_MASK) - SPECIAL_PAGES_SIZE) + +/* + * This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) + #define NUM_FPU_REGS 32 |